HDFS-7709. Fix findbug warnings in httpfs. Contributed by Rakesh R.

(cherry picked from commit 20660b7a67b7f2815b1e27b98dce2b2682399505)

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/fs/http/client/HttpFSUtils.java

@@ -17,6 +17,7 @@
  */
 package org.apache.hadoop.fs.http.client;
 
+import org.apache.commons.io.Charsets;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.fs.Path;
 import org.json.simple.parser.JSONParser;
@@ -127,7 +128,7 @@ public class HttpFSUtils {
   static Object jsonParse(HttpURLConnection conn) throws IOException {
     try {
       JSONParser parser = new JSONParser();
-      return parser.parse(new InputStreamReader(conn.getInputStream()));
+      return parser.parse(new InputStreamReader(conn.getInputStream(), Charsets.UTF_8));
     } catch (ParseException ex) {
       throw new IOException("JSON parser error, " + ex.getMessage(), ex);
     }

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/fs/http/server/HttpFSAuthenticationFilter.java

@@ -17,6 +17,7 @@
  */
 package org.apache.hadoop.fs.http.server;
 
+import org.apache.commons.io.Charsets;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.security.authentication.server.AuthenticationFilter;
@@ -24,8 +25,10 @@ import org.apache.hadoop.security.token.delegation.web.DelegationTokenAuthentica
 
 import javax.servlet.FilterConfig;
 import javax.servlet.ServletException;
-import java.io.FileReader;
+
+import java.io.FileInputStream;
 import java.io.IOException;
+import java.io.InputStreamReader;
 import java.io.Reader;
 import java.util.Map;
 import java.util.Properties;
@@ -77,7 +80,8 @@ public class HttpFSAuthenticationFilter
 
     try {
       StringBuilder secret = new StringBuilder();
-      Reader reader = new FileReader(signatureSecretFile);
+      Reader reader = new InputStreamReader(new FileInputStream(
+          signatureSecretFile), Charsets.UTF_8);
       int c = reader.read();
       while (c > -1) {
         secret.append((char)c);

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/lib/service/hadoop/FileSystemAccessService.java

@@ -177,7 +177,7 @@ public class FileSystemAccessService extends BaseService implements FileSystemAc
 
     String hadoopConfDirProp = getServiceConfig().get(HADOOP_CONF_DIR, getServer().getConfigDir());
     File hadoopConfDir = new File(hadoopConfDirProp).getAbsoluteFile();
-    if (hadoopConfDir == null) {
+    if (!hadoopConfDir.exists()) {
       hadoopConfDir = new File(getServer().getConfigDir()).getAbsoluteFile();
     }
     if (!hadoopConfDir.exists()) {

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/lib/wsrs/JSONMapProvider.java

@@ -18,6 +18,7 @@
 
 package org.apache.hadoop.lib.wsrs;
 
+import org.apache.commons.io.Charsets;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.json.simple.JSONObject;
 
@@ -55,7 +56,7 @@ public class JSONMapProvider implements MessageBodyWriter<Map> {
   public void writeTo(Map map, Class<?> aClass, Type type, Annotation[] annotations,
                       MediaType mediaType, MultivaluedMap<String, Object> stringObjectMultivaluedMap,
                       OutputStream outputStream) throws IOException, WebApplicationException {
-    Writer writer = new OutputStreamWriter(outputStream);
+    Writer writer = new OutputStreamWriter(outputStream,  Charsets.UTF_8);
     JSONObject.writeJSONString(map, writer);
     writer.write(ENTER);
     writer.flush();

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/lib/wsrs/JSONProvider.java

@@ -18,6 +18,7 @@
 
 package org.apache.hadoop.lib.wsrs;
 
+import org.apache.commons.io.Charsets;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.json.simple.JSONStreamAware;
 
@@ -55,7 +56,7 @@ public class JSONProvider implements MessageBodyWriter<JSONStreamAware> {
   public void writeTo(JSONStreamAware jsonStreamAware, Class<?> aClass, Type type, Annotation[] annotations,
                       MediaType mediaType, MultivaluedMap<String, Object> stringObjectMultivaluedMap,
                       OutputStream outputStream) throws IOException, WebApplicationException {
-    Writer writer = new OutputStreamWriter(outputStream);
+    Writer writer = new OutputStreamWriter(outputStream, Charsets.UTF_8);
     jsonStreamAware.writeJSONString(writer);
     writer.write(ENTER);
     writer.flush();

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -559,6 +559,8 @@ Release 2.7.0 - UNRELEASED
     in-memory state associated with volumes. (Lei (Eddy) Xu via Colin P.
     McCabe)
 
+    HDFS-7709. Fix findbug warnings in httpfs. (Rakesh R via ozawa)
+
 Release 2.6.1 - UNRELEASED
 
   INCOMPATIBLE CHANGES